{[CuSn₅Sb₃]²⁻}₂: A Dimer of Inhomogeneous Superatoms

Abstract

Reaction of the binary Zintl anion (Sn2 Sb2 )(2-) with the β-diketiminato complex [LCu(NCMe)] (L=nacnac=[(N(C6 H3 (i) Pr2 -2,6)C(Me))2 CH](-) ) in ethylenediamine or DMF affords the ternary cluster dimer {[CuSn5 Sb3 ](2-) }2 (1) as its [K(crypt-222)](+) salt. The chemical formulation of 1 is supported by energy-dispersive X-ray spectroscopy (EDX) and quantum chemical calculations. Each monomeric part of the dimer represents a trimetallic "[CuSn5 Sb3 ](2-) " cluster, with an architecture in between a tricapped trigonal prism and a capped square antiprism. As shown by quantum chemical investigations, the presence of Sb atoms and, in particular, of Cu atoms in the cluster skeleton makes the monomeric unit behave like an inhomogeneous superatom, which clearly prefers to dimerize, thereby producing a relatively short, yet virtually non-bonding Cu⋅⋅⋅Cu distance.

Superatomic Gallium Clusters in Dendrimers: Unique Rigidity and Reactivity Depending on their Atomicity

“…Therefore, the obtained clusters are strongly affected by their thermodynamic stability. [28] In this study, we demonstrate control of the valence electrons in superatomic gallium clusters [26,27,29,30] using our superatom synthesizer, that is, fourth generation dendritic polyphenylazomethines (DPAs). [31] Gallium is known to have a low melting point compared to other metals in the bulk state.…”

“…Although these approaches are sophisticated and allow variations in the clusters possible by changing the type of protecting ligands or synthesis conditions, they are basically thermodynamic syntheses. Therefore, the obtained clusters are strongly affected by their thermodynamic stability 28…”

[Co@Sn6Sb6]3−: An Off‐Center Endohedral 12‐Vertex Cluster

“…We recently reported that [K(crypt‐222)] 2 (Sn 2 Sb 2 ) reacts with [LCu(NCMe)] (L=nacnac=[(N(C 6 H 3 i Pr 2 ‐2,6)C(Me)) 2 CH] − ) in either 1,2‐diaminoethane (en) or dimethylformamide (DMF) to afford the dimer [(CuSn 5 Sb 3 ) 2 ] 4− as the [K(crypt‐222)] + salt . In this anion, the Cu + ions are not in endohedral positions, but rather are incorporated into the shells of the cluster monomers.…”

Evidence for the Existence of (SiP6H2)2– and its Homologs as Examples of Binary Nortricyclane‐Type Zintl Anions

“…We explore, which of the homoatomic motifs can be mimicked this way, in the sense of the pseudo element concept, or where there are limits owing to a misfit in atomic/ionic radii affording either no products or other structural motifs , . Furthermore, binary anions of the type ( E 14 2 E 15 2 ) 2– proved to be excellent precursors to larger multi‐metallic clusters . Recently, we extended this concept to the lighter P 4 analogue (Ge 2 P 2 ) 2– …”

“…By extraction of solid mixtures of the nominal compositions K 2 E 14 E 15 or K 2 E 14 2 E 15 2 (cf. the successful use of both stoichiometries as precursor solids for binary anions of other elemental combinations), , in en/crypt‐222, we obtained novel anions comprising seven atoms.…”